Malaria is a disease caused by the parasite Plasmodium, which is transmitted by the bite of an infected mosquito. Only the Anopheles genus of the mosquito can transmit Malaria. The symptoms of the disease include fever, vomiting, and/or headache. A characteristic malarial fever has ‘hot', ‘wet', and ‘cold' phases and appears 10 to 15 days after the mosquito bites. To diagnose malaria, blood slides are examined under a microscope, where the parasite is seen inside red blood cells. Rapid diagnostic test kits (RDTs) are used for diagnosing malaria in remote areas where microscopes cannot be used. 

Plasmodium vivax or P. falciparum are the most common malarial parasites, while P. malariae and P. ovale are other rarer forms. Of these, infection with P. falciparum is the most fatal if left untreated, possibly leading to kidney and brain complications, and even death. Chloroquine was the treatment of choice for malaria and is still followed in most countries for treatment of P. Vivax, but P. falciparum has developed resistance to it. As a result, Artemisinin-based combination therapy is now presently advised as the primary treatment for malaria. Among preventive measures, the use of insecticide treated nets at home and indoor residual spraying of insecticides are recommended for malaria. These precautions act by decreasing exposure to bites of infected mosquitoes. 

Key facts
  • Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected mosquitoes.
  • In the Americas, 481,788 cases of malaria and around 92 deaths were reported in 2022.
  • Malaria is preventable and curable.
  • Eighteen countries including one territory in the Region of the Americas are currently at risk of malaria.
  • Paraguay, Argentina, El Salvador, and Belize were certified malaria free by WHO in 2018, 2019, 2021, and 2023, respectively.
  • Three quarters of reported malaria cases in the region are caused by P. vivax.
  • Nine countries and one territory in this region are part of the E-2025 initiative: Belize, Costa Rica, the Dominican Republic, Ecuador, French Guyana, Guatemala, Honduras, Mexico, Panama and Suriname.
  • Malaria prevention in most countries relies on Indoor Residual Spraying (IRS), or mass or routine distribution of insecticide treated mosquito nets (ITNs).
  • Owing to the COVID-19 pandemic, diagnostic services were disrupted, as shown by the 32% decrease in malaria suspected cases tested in 2020 compared with 2019.

There are four types of human malaria:

  • Plasmodium falciparum
  • Plasmodium vivax
  • Plasmodium malariae
  • Plasmodium ovale
PAHO Response
  • The Plan of Action for Malaria Elimination 2021-2025 has been developed in consultation with countries and regional partners as a framework of reference to guide the efforts of countries and the contributions of donors and partners towards elimination of the disease in the Americas. 
  • The document seeks to guide national plans and promote an inter-programmatic- intersectoral approach, and joint efforts between countries and partners.
  • The Plan promotes a systematic action of detection, diagnosis, and response, which must be massively implemented and monitored programmatically.
  • In the document is remarked the need to address key malaria foci in each country with specific, information-based operational solutions.


Plan of Action for Malaria Elimination 2021-2025